In the related art, methods are known for synthesizing zeolite powder using a raw material solution that contains an alkali source and a silica source and in which zeolite seed crystals are dispersed (see, for example, WO2010/090049 and Japanese Unexamined Patent Application Publication No. 2004-83375).
In Patent Document 1, a raw material solution is prepared by mixing a silica source in which zeolite seed crystals are dispersed into an alkali source. In Patent Document 2, a raw material solution is prepared by adding an alkali source to a mixture of water and a silica source and, thereafter, dispersing zeolite seed crystals.